Axial flow type gas laser oscillator

Abstract

A gas laser oscillator achieving a substantial increase in laser output is provided. This gas laser oscillator includes a permeable screen plate at a position of a laser gas passage and can increase the laser output substantially by suppressing and uniformizing laser gas pulsation in a discharge tube.

1. A gas laser oscillator comprising:
 a discharge tube for exciting laser gas; 
 a laser gas passage connected to said discharge tube; 
 a laser gas circulator for circulating the laser gas in said laser gas passage as well as in said discharge tube; and 
 a permeable screen plate provided at a position of said laser gas passage; 
 wherein said laser gas circulator is provided at a position of said laser gas passage; 
 wherein said screen plate is provided between said laser gas circulator means and said discharge tube; 
 wherein said screen plate is meshed; and 
 wherein the following inequalities are satisfied:
   6.0×10 4  Pa·m 3 /min< Q×P< 1.5×10 6  Pa·m 3 /min 
     D/λ< 10 
     A/λ< 10 −2    
   0.2 <B/S< 0.7 
 
 where Q (m 3 /min) is a mass flow rate of the laser gas, P (Pa) is a pressure of the laser gas, λ(mm) is a wavelength of a compression wave in the laser gas that results from pressure fluctuation, D (mm) is an inside diameter of said laser gas passage in the vicinity of said screen plate, A (mm) is a mesh diameter of said screen plate, S (mm 2 ) is a total sectional area of said screen plate, and B (mm 2 ) is a total mesh area of said screen plate. 
 
   
   
     2. A gas laser oscillator comprising:
 a discharge tube for exciting laser gas; 
 a laser gas passage connected to said discharge tube; 
 a laser gas circulator for circulating the laser gas in said laser gas passage as well as in said discharge tube; and 
 a permeable screen plate provided at a position of said laser gas passage; 
 wherein said laser gas circulator is provided at a position of said laser gas passage; 
 wherein said screen plate is provided between said laser gas circulator and said discharge tube; 
 wherein said screen plate includes a plurality of holes; and 
 wherein the following inequalities are satisfied:
   6.0×10 4  Pa·m 3 /min< Q×P< 1.5×10 6  Pa·m 3 /min 
     D/λ< 10 
     A/λ< 10 −2    
   0.2 <B/S< 0.7 
 
 where Q (m 3 /min) is a mass flow rate of the laser gas, P (Pa) is a pressure of the laser gas, λ(mm) is a wavelength of a compression wave in the laser gas that results from pressure fluctuation, D (mm) is an inside diameter of said laser gas passage in the vicinity of said screen plate, A (mm) is a diameter of each of said holes, S (mm 2 ) is a total sectional area of said screen plate, and B (mm 2 ) is a total hole area of said screen plate. 
 
   
   
     3. The gas laser oscillator of  claim 1 , wherein said screen plate is joined to said laser gas passage by an elastic member. 
   
   
     4. The gas laser oscillator of  claim 1 , wherein said laser gas circulator is formed of a blower. 
   
   
     5. The gas laser oscillator of  claim 2 , wherein said screen plate is joined to said laser gas passage by an elastic member. 
   
   
     6. The gas laser oscillator of  claim 2 , wherein said laser gas circulator is formed of a blower.